|  |  | Summary

Now that you completed this chapter, you should have a firm understanding of the following: The combination of more powerful computers/workstations and network-intensive applications has created a need for bandwidth that is much greater than the 10 Mbps available on shared Ethernet/802.3 LANs. As more people utilize a network to share large files, access file servers, and connect to the Internet, network congestion occurs. A network can be divided in smaller units, called segments. Each segment is considered its own collision domain. In a segmented Ethernet LAN, data passed between segments is transmitted across the network by a bridge, switch, or router. A LAN that uses a switched Ethernet topology creates a network that behaves like it only has two nodes-the sending node and the receiving node. A switch segments a LAN into microsegments, creating collision-free domains from one larger collision domain. Switches achieve high-speed transfer by reading the destination Layer 2 MAC address of the packet, much the way a bridge does. This leads to a high rate of speed for packet forwarding. Ethernet switching increases the bandwidth available on a network by creating dedicated network segments (point-to-point connections) and connecting those segments in a virtual network within the switch. An asymmetric LAN switch provides switched connections between ports of unlike bandwidth, such as a combination of 10-Mbps and 100-Mbps ports. Symmetric switching is where all ports have the same bandwidth. Two switching modes can be used to forward frames through a switch: store-and-forward and cut-through. A VLAN is a grouping of network devices or users that is not restricted to a physical switch segment. The main function of the Spanning-Tree Protocol is to allow duplicate switched/bridged paths without suffering the latency effects of loops in the network.
| Threaded Case Study
Washington School District Project Task: User Requirements and Project Teams
After this chapter, you will begin studying the TCS Overview for the Washington School District Network Design Project. You will also be grouped in project teams, with each team assigned one school site. You need to complete the following tasks:

1. Familiarize yourself TCS Overview, including any activities your Instructor assigns.
2. Following the process decided upon by your instructor, you will be grouped into teams and assigned one of the following schools (for which there are detailed drawings)

| 1 | 2 | 3 | 4 | 5
Acacia | swf | bmp | swf | bmp | swf | bmp |  |  |  |
Desert View | swf | bmp | swf | bmp | swf | bmp | swf | bmp |  |
Mountain Sky | swf | bmp | swf | bmp | swf | bmp | swf | bmp |  |
RE Miller | swf | bmp | swf | bmp | swf | bmp |  |  |  |
Royal Palm | swf | bmp | swf | bmp | swf | bmp | swf | bmp | swf | bmp
Sunnyslope | swf | bmp | swf | bmp | swf | bmp | swf | bmp |  |
Sunset | swf | bmp | swf | bmp | swf | bmp |  |  |  |
All Zipped | swf | bmp |  |  |  |  |  |  |  |

1. Have your team download and organize all relevant files and tools necessary to begin your project.
2. Apply the CCNA Certification Exam Learning Objectives to your specific design. This will require a paragraph on how the learning objectives relate to your design. Learning objectives can be grouped together for the purpose of explanation. In this way, you will be studying for their CCNA Certification Exam as you work through the case study.

CCNA Certification Exam Learning Objectives (*** are explicit CCNA Exam objectives; unmarked are knowledge assumed by the exam):

LAN Switching

- Describe the advantages of LAN segmentation.
- Describe LAN segmentation using bridges.***
- Describe LAN segmentation using routers.***
- Describe LAN segmentation using switches.***
- Describe the benefits of network segmentation with bridges.***
- Describe the benefits of network segmentation with routers.***
- Describe the benefits of network segmentation with switches.***
- Name and describe two switching methods.***
- Distinguish between cut-through and store-and-forward switching.***
- Define and describe the function of a MAC Address.***

Ethernet

- Describe network congestion problem in Ethernet networks.***
- Describe full- and half-duplex Ethernet operation.***
- Describe the features and benefits of Fast Ethernet.***
- Describe the guidelines and distance limitations of Fast Ethernet.***

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